At a hospital in Pittsburgh, surgeons are now allowed to place patients into a state of suspended animation. If a patient arrives with a traumatic injury, and attempts to restart their heart have failed — if they’re on the doorstep of death — they will have their blood replaced with a cold saline solution, which stops almost all cellular activity. At this point, the patient is clinically dead — but if the doctors can fix the injury within a few hours, they can be returned to life from suspended animation by replacing the saline with blood.

Or at least, that’s the theory. The technique of suspended animation (or “emergency preservation and resuscitation” as non-sci-fi doctors prefer to call it) was first trialed on pigs in 2002.....